<template>
  <div class="xtx-numbox">
    <div class="label" v-if="label">数量</div>
    <div class="numbox">
      <a @click="changeNum(-1)" href="javascript:;" >-</a>
      <input type="text" readonly :value="modelValue">
      <a @click="changeNum(1)" href="javascript:;">+</a>
    </div>
    <!-- <div class="numbox">
      <a @click="changeNum(-1)" href="javascript:;" >-</a>
      <input v-model="modelValue1">
      <a @click="changeNum(1)" href="javascript:;">+</a>
    </div> -->
  </div>
</template>

<script>
import { useVModel } from '@vueuse/core'
export default {
  name: 'XtxNumbox',
  props: {
    label: {
      type: Boolean,
      default: true
    },
    modelValue: {
      type: Number,
      default: 1
    },
    min: {
      type: Number,
      default: 1
    },
    max: {
      type: Number,
      default: 100
    }
  },
  setup (props, { emit }) {
    // 绑定按钮点击事件 -按钮 +按钮 触发同一个事件（函数）
    // 使用vueuse的useVModel做双向数据绑定,修改count通知父组件count
    const count = useVModel(props, 'modelValue', emit)
    const changeNum = (step) => {
      // 得到将要改变的值 如果值不合法 终止程序的运行
      const newValue = count.value + step
      if (newValue < props.min || newValue > props.max) return
      // 正常情况
      count.value += step
      // 提供change事件
      emit('change', newValue)
    }
    return { changeNum }
  }
}
</script>

<style lang="less" scoped>
.xtx-numbox{
  display: flex;
  align-items: center;
  .label{
    width: 60px;
    color: #999;
    padding-left: 10px;
  }
  .numbox{
    margin-left: 5px;
    width: 120px;
    height: 30px;
    border:1px solid #e4e4e4;
    display: flex;
    >a{
      width: 29px;
      line-height: 28px;
      background: #f8f8f8;
      text-align: center;
      font-size: 16px;
      color: #666;
      &:first-of-type{
        border-right: 1px solid #e4e4e4;
      }
      &:last-of-type{
        border-left: 1px solid #e4e4e4;
      }
    }
    >input{
      width: 60px;
      padding: 0 5px;
      text-align: center;
      color:#666;
    }
  }
}
</style>
